OPTICAL PARTS FOR ENDOSCOPE, ENDOSCOPIC LENS SYSTEM AND ENDOSCOPE

摘要

PROBLEM TO BE SOLVED: To provide optical parts for an endoscope having excellent chemical resistance to various chemicals. SOLUTION: The optical parts for the endoscope consist of glass as a component material. The glass has the following properties (1) to (3): The property (1): The refractive index nd of this glass is 1.54 to 1.64. The nature (2): The Abbe numberνof the glass is 35 to 45. The nature (3): The yield point of the glass is <=500 deg.C. The Knoop hardness Hk of the glass is preferably 380 to 480 deg.C.